Fatty salad dressings like ranch or blue cheese are often cited as a no-no by nutritionists if you want to keep a salad healthy. However, new research published in Molecular Nutrition and Food Research suggests that some fattier dressings do a better job of unlocking the health benefits of vegetables than their low-fat counterparts.

The study itself was small, but as the Atlantic points out, the science behind it isn't anything new. It's all about different nutrients working together. Test subjects were fed three types of dressing with their salads: one with saturated fat, one with polyunsaturated fat, and one with monounsaturated fat. The winner? Monounsaturated fat (aka canola oil):

Carotenoids, which include lycopene and beta-carotene, have been proven to help reduce the risk for heart disease and other chronic illnesses, so the more you get, the better. They found that subjects who had eaten the canola oil dressing had the highest levels of carotenoids in their bloodstream. Moreover, those who'd had dressings based on butter or vegetable oil needed more dressing to achieve the same benefits.

As with anything it's all about balance, but if you're not desperately trying to cut calories this research suggests dressings made with canola oil might help unlock some of the benefits vegetables have to offer. If nothing else they'll taste a bit better in the process.